U.S. patent application number 09/906556 was filed with the patent office on 2002-03-14 for automatic chord progression correction apparatus and automatic composition apparatus.
This patent application is currently assigned to YAMAHA CORPORATION. Invention is credited to Aoki, Eiichiro.
Application Number | 20020029685 09/906556 |
Document ID | / |
Family ID | 18713112 |
Filed Date | 2002-03-14 |
United States Patent
Application |
20020029685 |
Kind Code |
A1 |
Aoki, Eiichiro |
March 14, 2002 |
Automatic chord progression correction apparatus and automatic
composition apparatus
Abstract
For both an automatic chord correction and an automatic
composition, it is required to correct a part of a series of given
chords in order to have a musically natural connection between
adjacent chords. A series of chords "a", "b", "c", "d", "e", "f"
(each letter means one kind of chords) for a music is selected by a
user. If two chords "c" and "d" among the series of chords "a",
"b", "c", "d", "e", "f" are changed into different ones, according
to the user's preference or to make them more appropriate to the
motif melody, the chord "b" adjacent to the changed "c" is
automatically corrected into "b*" so that both chord connections
from "a" to "b*" and from "b*" to the changed "c" can be more
musically natural. Similarly, the chord "e" adjacent to the changed
"d" is automatically corrected into "e*" so that both chord
connections from the changed "d" to "e*" and from "e*" to "f" can
be more musically natural.
Inventors: |
Aoki, Eiichiro;
(Hamamatsu-shi, JP) |
Correspondence
Address: |
ROSSI & ASSOCIATES
P.O. BOX 826
ASHBURN
VA
20146-0826
US
|
Assignee: |
YAMAHA CORPORATION
|
Family ID: |
18713112 |
Appl. No.: |
09/906556 |
Filed: |
July 16, 2001 |
Current U.S.
Class: |
84/613 |
Current CPC
Class: |
G10H 1/38 20130101; G10H
2210/101 20130101; G10H 2210/576 20130101 |
Class at
Publication: |
84/613 |
International
Class: |
G10H 001/38 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 18, 2000 |
JP |
2000-218107 |
Claims
What is claimed is:
1. A chord progression correction apparatus comprising: chord
change means for changing a part of a series of given chords; and
chord correction means for correcting a chord adjacent to the
changed part to generate a new series of chords bringing a
musically natural chord connection.
2. The chord progression correction apparatus as claimed in claim
1, wherein the chord correction means includes: a table memorizing
conditions for a musically natural chord connection; and chord
determination means for determining the chord adjacent to the
changed part by referring to the table according to two chords
which are positioned on the both sides of the chord adjacent to the
changed part, one of the two chords being included in the changed
part, and another one of the two chords being included in the
series of given chords.
3. A chord progression correction apparatus comprising: chord
change section which changes a part of a series of given chords;
and chord correction section which corrects a chord adjacent to the
changed part to generate a new series of chords bringing a
musically natural chord connection.
4. A method for correcting a chord progression comprising the steps
of: changing a part of a series of given chords; and correcting a
chord adjacent to the changed part to generate a new series of
chords bringing a musically natural chord connection.
5. A method for correcting a chord progression as claimed in claim
4, wherein the chord adjacent to the changed part is determined by
referring to a condition table according to two chords which are
positioned on the both sides of the chord adjacent to the changed
part, one of the two chords being included in the changed part, and
another one of the two chords being included in the series of given
chords, wherein the condition table memorizes conditions for a
musically natural chord connection.
6. A method for correcting a chord progression as claimed in claim
4, wherein the step of correcting a chord includes the steps of:
analyzing the series of given chords to detect a feature of the
series of given chords; and determining the chord adjacent to the
changed part by referring to a condition table according to the
detected feature of the series of given chords and two chords which
are positioned on the both sides of the chord adjacent to the
changed part, one of the two chords being included in the changed
part, and another one of the two chords being included in the
series of given chords, wherein the condition table memorizes
conditions for a musically natural chord connection.
7. A computer readable storage medium storing a computer program
applicable to a chord progression correction apparatus, the
computer program comprising the steps of: changing a part of a
series of given chords; and correcting a chord adjacent to the
changed part to generate a new series of chords bringing a
musically natural chord connection.
8. A chord progression correction apparatus which replaces a part
of a series of given chords by a chord appropriate to a given
melody, comprising: detection means for detecting a chord
appropriate to the given melody and whose connection with the
series of given chords is musically natural; and chord replacement
means for replacing a part of the series of given chords by the
detected chord.
9. A chord progression correction apparatus as claimed in claim 8,
wherein the chord detection means comprises: chord list up means
for listing up a plurality of chords appropriate to the given
melody; and chord determination means for determining one chord
from among the plurality of listed up chords to bring a musically
natural connection with the series of given chords.
10. A chord progression correction apparatus which replaces a part
of a series of given chords by a chord appropriate to a given
melody, comprising: detection section which detects a chord
appropriate to the given melody and whose connection with the
series of given chords is musically natural; and chord replacement
section which replaces a part of the series of given chords by the
detected chord.
11. A chord progression correction method which replaces a part of
a series of given chords by a chord appropriate to a given melody,
comprising the steps of: detecting a chord appropriate to the given
melody and whose connection with the series of given chords is
musically natural; and replacing a part of the series of given
chords by the detected chord.
12. A chord progression correction method as claimed in claim 11,
wherein the step of detecting a chord includes the steps of:
listing up a plurality of chords appropriate to the given melody;
and determining one chord from among the plurality of listed up
chords to bring a musically natural connection with the series of
given chords.
13. A chord progression correction method as claimed in claim 12,
wherein at least one note of plurality of notes which constitute
each chord of the plurality of listed up chords is coincident with
at least one note included in the given melody.
14. A chord progression correction method as claimed in claim 11,
wherein the step of detecting a chord includes the steps of:
listing up a plurality of chords appropriate to the given melody;
and determining one chord from among the plurality of listed up
chords to bring a musically natural connection with the series of
given chords by referring to a table which memorizes conditions for
a musically natural chord connection.
15. A chord progression correction method as claimed in claim 11,
wherein the step of detecting a chord includes the steps of:
analyzing the series of given chords to detect a feature of the
series of given chords; listing up a plurality of chords
appropriate to the given melody; selecting a plurality of chords
satisfying the detected feature from among the plurality of listed
up chords; determining one chord from among the plurality of
selected chords to bring a musically natural connection with the
series of given chords.
16. A chord progression correction method as claimed in claim 11,
wherein the step of detecting a chord includes the steps of:
analyzing the series of given chords to detect a feature of the
series of given chords; listing up a plurality of chords
appropriate to the given melody; selecting a plurality of chords
satisfying the detected feature from among the plurality of listed
up chords; determining one chord from among the plurality of
selected chords to bring a musically natural connection with the
series of given chords by referring to a table which memorizes
conditions for a musically natural chord connection.
17. A computer readable storage medium storing a computer program
applicable to a chord progression correction apparatus, the
computer program comprising the steps of: detecting a chord
appropriate to the given melody and whose connection with the
series of given chords is musically natural; and replacing a part
of the series of given chords by the detected chord.
18. An automatic composition apparatus which automatically composes
a music with both given melody generation data relating to a
musically highlighted portion and a series of given chords,
comprising: addition means for adding the musically highlighted
portion as a part of a music; and setting means for setting both
the melody generation data relating to the musically highlighted
portion and a part of chords corresponding to the musically
highlighted portion among the series of given chords for the added
musically highlighted portion.
19. An automatic composition apparatus as claimed in claim 18
further comprising: chord correction means for correcting a chord
set for the added musically highlighted portion to bring a
musically natural connection with the series of given chords.
20. An automatic composition apparatus as claimed in claim 18
further comprising: transposition data adding means for adding
transposition data defining a nature of transposition to the melody
generation data assigned at the added musically highlighted
portion.
21. An automatic composition apparatus which automatically composes
a music with both given melody generation data relating to a
musically highlighted portion and a series of given chords,
comprising: addition section which adds the musically highlighted
portion as a part of a music; and setting section which sets both
the melody generation data relating to the musically highlighted
portion and a part of chords corresponding to the musically
highlighted portion among the series of given chords for the added
musically highlighted portion.
22. An automatic composition method which automatically composes a
music with both given melody generation data relating to a
musically highlighted portion and a series of given chords,
comprising: adding the musically highlighted portion as a part of a
music; and setting both the melody generation data relating to the
musically highlighted portion and a part of chords corresponding to
the musically highlighted portion among the series of given chords
for the added musically highlighted portion.
23. A computer readable storage medium storing a computer program
applicable to an automatic composition apparatus which
automatically composes a music with both given melody generation
data relating to a musically highlighted portion and a series of
given chords, the computer program comprising the steps of: adding
the musically highlighted portion as a part of a music; and setting
both the melody generation data relating to the musically
highlighted portion and a part of chords corresponding to the
musically highlighted portion among the series of given chords for
the added musically highlighted portion.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates firstly to a chord progression
correction apparatus which modifies a part of a series of chords in
order to make it more musically appropriate, to a method of such
chord progression correction, and to a computer readable storage
medium storing a computer program applied to the apparatus.
Secondly, it relates to an automatic composition apparatus which
automatically generates a melody of a complete music with given
melody generation data relating to a musically highlighted portion
and a series of given chords, to a method of such automatic
composition, and to a computer readable storage medium storing a
computer program applied to the apparatus.
[0003] 2. Description of the Related Art
[0004] It is already known, in an electronic music system, that a
series of chords selected by a user from among plural series of
chords prepared beforehand according to a chord progression rule,
can be added to a melody performed by a user or played
automatically. It has also become an established knowledge that a
complete melody of music can be composed automatically by using an
adequate series of chords selected from among plural series of
chords, and necessary data particularly inputted for musical melody
generation which corresponds to various musical elements such as
musical nuance, music key, motif melody, musical structure,
information of pitch(e.g., register, pitch fluctuation).
[0005] In both cases when an adequate series of chords is to be
given to a melody performance or automatic melody play and when a
proper melody is to be automatically composed, it is often desired
to particularize a music by modifying a part of the selected chord
corresponding to a special portion of musical motif or musically
highlighted portion. However, if a part of such selected set of
chords is too easily changed by user's primitive preference or
hasty aim to fit better to a given motif melody, the chord
progression often becomes less smooth and subject to miss
naturalness at the point before and after such chord connection.
Additionally, it has not yet been proposed in any of prior arts to
compose a music automatically in consideration of "musically
highlighted portion" mentioned above.
SUMMARY OF THE INVENTION
[0006] In order to deal with the aforementioned problem, it is an
object of the present invention to provide a chord progression
correction apparatus which generates no defect of unnaturalness at
the chord connection point when a part of a series of chords is
changed, to provide a chord progression correction method of the
same function, and to provide a computer readable storage medium
applied to the chord progression correction apparatus. It is also
an object of the invention to provide an automatic composition
apparatus in consideration of the "musically highlighted portion",
an automatic composition method of the same function, and a
computer readable storage medium storing a program applied to the
automatic composition apparatus.
[0007] In order to achieve the aforesaid object, the first
characteristic feature of this invention lies in an automatic chord
progression correction apparatus, the apparatus comprising chord
change means for changing a part of a series of given chords and
chord correction means for correcting a chord adjacent to the
changed part to generate a new series of chords bringing a
musically natural chord connection.
[0008] The above mentioned chord correction means includes, for
instance, a table memorizing conditions for a musically natural
chord connection, and chord determination means for determining the
chord adjacent to the changed part by referring to the table
according to two chords which are positioned on the both sides of
the chord adjacent to the changed part, one of the two chords being
included in the changed part, and another one of the two chords
being included in the series of given chords.
[0009] From another viewpoint, the first feature of the invention
lies both in a chord progression correction method based on the
idea corresponding to the chord progression correction apparatus
and in a computer readable storage medium which stores the program
of the same function.
[0010] According to the first feature of the invention, when a part
of the series of given chords is changed either by user's
preference or in order to make more appropriate to a given motif
melody, a new series of chords can be generated automatically to
make the chord connection musically more natural by correcting a
chord adjacent to the changed chord found in the series of given
chord. Therefore, a musically desired chord progression can always
be obtained, even if a part of a series of given chords is changed
under various conditions.
[0011] The second characteristic feature of this invention lies in
a chord progression correction apparatus which replaces a part of a
series of given chords by a chord appropriate to a given melody,
the apparatus comprising detection means for detecting a chord
appropriate to the given melody and whose connection with the
series of given chords is musically natural, and chord replacement
means for replacing the part of the series of given chords by the
detected chord.
[0012] The above mentioned chord detection means, for instance,
comprises chord list up means for listing up a plurality of chords
appropriate to the given melody, and chord determination means for
determining one chord from among the plurality of listed up chords
to bring a musically natural connection with the series of given
chords.
[0013] From another standpoint, the second feature of this
invention lies both in a chord progression correction method based
on the idea corresponding to the chord progression correction
apparatus and in a computer readable storage medium which stores
the program of the same function.
[0014] According to the second feature of the invention, when a
part of a series of given chords is to be replaced by a different
chord which fits more favorably a given melody, an appropriate
chord is detected for the given melody and its chord progression in
connection with the series of given chords becomes musically
natural. Then, the part of the series of given chords is replaced
by the detected chord is. Therefore, in case of an automatic
composition system too, when a part of a series of given chords is
aimed to be replaced to fit better a given motif melody, a
musically natural chord progression can be automatically
obtained.
[0015] The third characteristic feature of this invention lies in
an automatic composition apparatus which automatically composes a
music with both given melody generation data relating to a
musically highlighted portion and a series of given chords, the
apparatus comprising addition means for adding the musically
highlighted portion as a part of a music, and setting means for
setting both the melody generation data relating to the musically
highlighted portion and a part of chords corresponding to the
musically highlighted portion among the series of given chords for
the added musically highlighted portion.
[0016] According to the third feature of the invention, it becomes
possible to compose automatically a music with full of variety by
placing a given musically highlighted passage at the beginning
and/or the end of a music or by using it repetitively in a music so
that the music may have several outstanding portions.
[0017] Preferably, the above mentioned automatic composition
apparatus further comprises chord correction means for correcting a
chord set for the added musically highlighted portion to bring a
musically natural connection with the series of given chords. With
such additional chord correction means, the given chord progression
does not give unnatural impression when a musically highlighted
portion is added, which makes the automatic composition apparatus
be capable of composing automatically musical pieces of high
quality.
[0018] Preferably, the above mentioned automatic composition
apparatus further comprises transposition data adding means for
adding transposition data defining a nature of transposition to the
melody generation data assigned at the added musically highlighted
portion. With such transposition data adding means, the
automatically composed music can have still richer highlighted
passages.
[0019] From another point of view, the third feature of this
invention lies both in an automatic composition method based on the
idea corresponding to the automatic composition apparatus and in a
computer readable storage medium which stores the program of the
same function.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] For better understanding of the above and other features of
the present invention, the preferred embodiments of the invention
will be described in greater detail below with reference to the
accompanying drawings, in which:
[0021] FIG. 1 shows a block diagram of an electronic musical sound
generation apparatus as a whole embodiment of this invention;
[0022] FIG. 2 is a flow chart of a chord progression generation
program executed by CPU in FIG. 1 applying the first chord
correction method;
[0023] FIG. 3 is a flow chart of an automatic composition program
executed by CPU in FIG. 1 applying the first chord correction
method;
[0024] FIG. 4 shows a diagram of a series of chords to explain the
way of the first chord correction;
[0025] FIG. 5 shows an example of the series of chords in FIG.
4;
[0026] FIG. 6 is a flow chart of a chord progression generation
program executed by CPU in FIG. 1, applying the second chord
correction method;
[0027] FIG. 7 shows a diagram of a series of chords to explain the
way of the second chord correction;
[0028] FIG. 8 shows an example of the series of chords in FIG.
7;
[0029] FIG. 9 shows an example of music piece containing musically
highlighted portions;
[0030] FIG. 10 is a flow chart of another automatic composition
program executed by CPU in FIG. 1, applying the first and the
second chord correction method; and,
[0031] FIG. 11 is an example of displayed information according to
the automatic composition program of FIG. 10.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0032] Other objects and advantages of the present invention will
be readily understood by those skilled in the art from the
following description of preferred embodiments of the present
invention in conjunction with the accompanying drawings of
which;
[0033] FIG. 1 is a diagram of an electronic musical sound
generation apparatus as a whole, including a chord progression
correction apparatus and an automatic composition apparatus as an
embodiment of this invention.
[0034] The musical sound generation apparatus is equipped with
Group of Input Devices for Performance 11, Group of Manipulating
Knobs 12 and Display Unit 13. Group of Input Devices for
Performance 11 is constituted, for example, of a keyboard having a
plurality of black and white musical keys, and is operated for
performance by a user to indicate generation of musical sound,
pitch of generated musical sounds etc. The Group of Manipulating
Knobs 12 is disposed on an operation panel and is operated to
indicate timbre, volume of generated sounds, displayed content of
Display Unit 13, and is used to input necessary data for correction
of chord progression and control of automatic composition. Other
operating devices such as a set of ten-keys, cursor keys, mouse are
included in the Group of Manipulating Knobs 12 in this description.
Each operation of these Group of Input Devices for Performance 11
and Group of Manipulating Knobs 12 is detected respectively by
Detecting Circuits 14, 15 connected to Bus 20. Display Unit 13,
constituted of devices like CRT or LCD, displays various kinds of
information in characters and figures, and is controlled by Display
Control Circuit 16 connected to Bus 20.
[0035] The musical sound generation apparatus has also Sound Source
Circuit 17 and Effect Circuit 18, both connected to Bus 20. Sound
Source Circuit 17 has a plurality of musical sound signal
generation channel to form a musical sound signal based on the
performance information (i.e., key code, key-on signal, key-off
signal, timber information etc.) furnished from Bus 20, and is
capable of generating plural number of musical sound signals
simultaneously. Effect Circuit 18 adds various kinds of effect in
accordance with effect control parameters received via Bus 20 to
the musical sound signals outputted from Sound Source Circuit 17.
To this Effect Circuit 18 are connected D/A converter and Sound
System 19 comprising amplifiers and loud speakers. The sound
processed with effect is then radiated from Sound System 19.
[0036] CPU 21, ROM 22 and RAM 23 having a principal role of the
micro computer are connected to Bus 20. CPU 21 executes various
programs to control the whole musical sound generation apparatus.
Timer 24 is connected to CPU 21 to provide CPU21 with necessary
timing information for its execution of the various programs. ROM
22 memorizes a part of the programs executed by CPU 21 and a part
or all of the data to be utilized for execution of the programs.
RAM 23 memorizes temporarily a part of the above mentioned various
programs and a part or all of the above mentioned data received
during execution of the programs as well as values of the variables
necessary for execution of the programs.
[0037] To Bus 20 are also connected External Storage Device 31,
MIDI(=Musical Instruments Digital Interface) Interface 32 and
Transmission Interface 33. External Storage Device 31 consists of
data storage medium(s) such as hard disk, flexible disk, CD-ROM,
MO(magneto-optical disk), DVD(digital video disk), semi- conductor
memory which are either removable from or non-removably embedded to
the system and whose memorized content can be read by a computer,
and its driving device which enables the storage medium to read and
write programs and data. This External Storage Device 31 also
memorizes a part of the various programs and a part or all of the
above mentioned various data, which are not memorized in ROM 22.
Those programs and data memorized in External Storage Device 31 are
sometimes directly accessed by CPU 21, but in general, they are
once transferred to RAM 23 and then, used at subsequent steps.
[0038] MIDI Interface 32 is connected to Other Devices Equipped
with MIDI Interface 34 (hereinafter called MIDI Devices 34) such as
performance devices like a keyboard, other musical instruments,
personal computers, automatic play apparatuses(or sequencers). MIDI
Interface 32 functions as an interface when MIDI information is
received from and/or sent to MIDI Devices 34.
[0039] Transmission Interface 33 is connected to Server Computer 36
via Transmission Network 35 which is in either wired or wireless
structure, to receive and/or send data and programs from and/or to
Server Computer 36. It is also possible to forward from Server
Computer 36 the programs and/or the data to External Storage Device
31 or RAM 23 via Transmission Network 35 and Transmission Interface
33 to utilize them at subsequent steps.
[0040] b. Example of chord progression correction process
[0041] Not only describing an example of chord progression
correction process which is directly related to the present
invention, but a general reason why chord progression correction is
desired and what kind of chord progression process is applied to
the process of chord progression correction of this invention will
now be explained.
[0042] When a series of chords is going to be added to a melody
performed by a user or automatically played, the user starts up
"chord progression generation program" shown in FIG. 2 and
memorized in ROM 22 or External Storage Device 31. The execution of
this "chord progression generation program" begins at step 100 and
a series of chords is determined at step 102.
[0043] In the process of determining a series of chords, CPU 21
firstly indicates to select a series of chords by displaying it on
Display Unit 13. Then the user, in response, selects a certain
series of chords from among plural series of chords prepared
beforehand and stored in External Storage Device 31, by operating
Group of Manipulating Knobs 12. It is also possible, at the moment
of starting up "chord progression generation program", a number of
series of chords stored in Eternal Storage Device 31 are forwarded
to RAM 23, and the chord series selection is made among the number
of series of chords readable from RAM 23. Each series of chords is
composed of a plurality of chords which were prepared by following
given rules of chord progression, and all of which should bring a
musically natural chord connection. In the determining process, the
user can use, if he prefers, a sorting function for the chord
series selection by designating the desired conditions one by one,
for example, major or minor chord, bright or dark impression, etc.
to arrive finally at the selected series of chords. During the
above mentioned process to input a series of chords, either Group
of Input Devices for Performance 11 or Group of Manipulating Knobs
12 can also be utilized instead.
[0044] Next, CPU 21 suggests the user, by displaying on Display
Unit 13, to change a series of chords step 104, and accepts user's
chosen change in a part of the series of chords once determined. In
case of adding a series of chords to a melody performed by a user
or played automatically, it often happens that the user desires to
change a part of the series of chords determined once, namely, the
part corresponding to a motif portion and/or other musically
highlighted portion in a whole music so that the music may become
more attractive. In such case, the user can change the part of the
determined series of chords into different chords, insert a new
chord among the series of chords, delete a part of the series of
chords, or he can copy a part of the series of chords to paste it
to another part of the series of chords either by using Group of
Input Devices for Performance 11 or by Group of Manipulating Knobs
12.
[0045] After such process of step 104, both chords found before and
after the changed chord at step 104 are automatically corrected in
order to make musical impression at the connection point more
favorable, at step 106, and the execution of the "chord progression
generation program" terminates at step 108. As the process at step
106 is directly related to this invention, it will later be
described again in detail. Through the execution of such chord
progression generation program", a series of chords is finally
determined.
[0046] In the next paragraph, an explanation will be given to the
case when the chord progression correction related to this
invention is applied to an automatic composition apparatus which
composes automatically musical melodies. At first, the user starts
up the automatic composition program of FIG. 3 stored in ROM 22 or
External Storage Device 31. The execution of this "automatic
composition program" begins at step 120 and necessary data for
melody generation are inputted at step 122.
[0047] In the process of inputting the data for melody generation,
CPU 21 displays the indication of melody generation data input on
Display Unit 13. Then a user, in response, inputs data for melody
generation by operating Group of Input Devices for Performance 11
or by Group of Manipulating Knobs 12. The data for melody
generation comprise parameters corresponding to musical nuance,
music key, motif melody, music structure(=combination of plural
musical paragraphs), pitch information(=register, pitch fluctuation
etc.), rhythm information(=number of notes, syncopation etc.)
etc.
[0048] Then, CPU 21 executes chord progression generation process
at step 124. The chord progression generation process is almost
identical to the "chord progression generation program" in FIG. 2
except a part of steps 102 and 104. Namely, at step 102, it is
possible, in addition to the above mentioned process, to determine
a series of chords by using some of the parameters such as musical
nuance, music key, motif melody, music structure which are inputted
at step 122. This is especially an efficient way when a series of
chords should be selected from among a number of series of chords
stored in External Storage Device 31.
[0049] At the process of step 104, it is possible to change
automatically a part of the determined series of chords by the
melody generation data inputted at step 122, either in addition to
or instead of the chord change process by either Group of Input
Devices for Performance 11 or Group of Manipulating Knobs 12. For
example, the most adequate chord(or chord progression) to the motif
melody can be detected based on the motif melody itself inputted at
step 122. Then, the detected chord is inserted into a proper
position in the determined (at step 102) series of chords, or it
replaces a certain chord existing there.
[0050] After the process at step 124, one suitable musical scale
mode is detected at step 126 among various kinds of musical scale
mode, such as Ionian mode, Lydian mode, Mixolydian mode, Dorian
mode based on the determined series of chords at step 124. The
musical scale mode is selected according to the kind of chords
constituting the determined series of chords, because the kind of
chord is limited in accordance with the specialized musical scale
mode. As this musical scale mode detection is not essentially
related to this invention, further explanation is abbreviated
here.
[0051] At the next step 128, a melody is generated automatically,
then execution of the "automatic composition program" is terminated
at step 130. A melody is composed automatically, based on the
inputted data for melody generation, the determined series of
chords and the detected musical scale mode. As the automatic
composition itself is not directly related to chord progression
correction of this invention, detailed description is here
abbreviated.
[0052] C. The first chord correction method
[0053] In this paragraph, the first way of chord correction will be
explained in detail. This is applied to the case when a chord is
changed either manually or automatically according to the motif
portion of a music as described in the above. The chords placed
before and after the changed chord are corrected automatically by
the process of step 106 in FIG. 2.
[0054] FIG. 4 shows an example of the series of chords determined
at the above mentioned step 102 in a form of ". . . , a, b, c, d,
e, f., . . . ". The chords "c" and "d" are the ones changed either
manually or automatically at step 104. The chords located before
the chord "a" and after the chord "f" remain unchanged from the one
in the series of given chord, and the chord "b" and "e" are the
ones to be corrected automatically into "b*" and "e*" respectively.
Namely, the chord "b" is corrected into "b*" which has a musically
natural connection with both chord "a" and chord "c", and the chord
"e" is corrected into "e*" which has a musically natural connection
with both chords "d" and "f".
[0055] Each of the above mentioned chords "a", "b", "c", "d", "e",
"f" expresses a kind of chord and it is not necessary for each one
to have a constant length (i.e., number of measures, beats). For
instance, a measure can fully be occupied by one chord "e", or two
earlier beats of a measure can be occupied by "e" and the rest by
"f".
[0056] c1. . Determination of the correction chord "e*"
[0057] An example of correction process of the chord "e" is herein
below described. The changed chords "c" and "d" belong to a motif
portion of the music, and this motif portion is generally placed at
the melody part "A" and/or the melody part "B", namely at the head
of a block. Accordingly, as the chord "d" cannot be musical
punctuation due to its position enough close to the head position,
the chord connection between the chords "d" and "e" can be made
despite the ending impression. Each of the melody parts A and B
signifies one musical paragraph among a plurality of paragraphs
which constitutes a music.
[0058] The detailed procedure of the process in step 106, will be
described hereafter.
[0059] <Procedure 1>
[0060] The progression of the series of chords determined at the
process of step 102 in FIG. 2 is analyzed to detect its feature
automatically. The feature can be recognized by such expressions as
"the chord consists uniquely of diatonic chord (=a chord
constituted of plural notes selected from among seven notes in
diatonic scale)", "the chord consists only of triad (=chord
constituted of three notes)". When the feature of the series of
chords is already inputted by making use of sorting function at the
step 102 to determine the series of chords, it is recommended to
use the inputted feature of the series of chords, instead of the
detection of the feature of the series of chords, or in addition to
the detected feature of the series of chords.
[0061] <Procedure 2>
[0062] The chord "e*" is determined, referring Table 1 shown below,
so that both chord connections from "d" to "e*" and from "e*" to
"f" may be musically natural. The chord progressions in Table 1 are
expressed by the interval between two roots of a pair of chords and
by the direction of progression between two roots. For instance,
"+4th perfect", "-2nd minor", and "-2nd major" signify "root will
go up 4th perfect intervals", "root will go down 2nd minor
intervals" and "root will go down 2nd major intervals"
respectively. Chord progressions shown in the tables cited
afterwards are expressed also by the interval between two roots and
by the chord change direction. Such data in the tables are stored
in External Storage Device 31 in a table format. In Table 1, if the
chord "e*" exists in both columns of priority 1, all such "e*"
chords are listed up as candidate to be selected. If there is no
"e*" in any columns of priority 1, columns of priority 2, 3, etc.,
shall be searched, in order to find out next candidates to be
eventually listed up.
1TABLE 1 Priority Progression "d"-"e*" Progression "e*"-"f" 1 +4th
perfect - 2nd minor, -2nd major -2nd minor, -2nd major + 4th
perfect +4th perfect -3rd minor, -3rd major, +3rd minor -3rd minor,
-3rd major, +4th perfect +3rd minor 4th augmented("d" is 7.sup.th
+4th perfect dim.) +2nd major +2nd major +2nd minor +2nd minor +3rd
major +3rd major +3rd minor +3rd minor 2 -3rd minor, -3rd major,
-2nd minor, -2nd major, +5th perfect +5th perfect -2nd minor, -2nd
major, -3rd minor, -3rd major, +5th perfect +5th perfect . . . . .
. . . .
[0063] <Procedure 3>
[0064] If the chords listed up in the above way includes the chord
"e" which was determined at the process of step 102, the chord "e"
is replaced by the correction chord "e*". If the chord "e" is not
found in the list, the correction chord "e*" is selected from among
the listed chords by finding the one which satisfies the features
detected in the procedure 1. If there are plural chords satisfying
the conditions, one chord can be selected from among them as the
correction chord "e*", at random or by the user's any idea.
[0065] <Procedure 4>
[0066] In case when the chord "d" is a special (relatively unusual,
e.g., diminish chord "dim"), neither way of chord selection
described in Procedure 1 nor 2 should be adopted. The correction
chord "e*" is determined according to priority shown in the
following Table 2.
2TABLE 2 Priority Progression "d"-"e*" Progression "e*"-"f" 1 +2nd
minor +2nd minor, -2nd minor 2 -2nd minor +2nd minor, -2nd minor .
. . . . . . . .
[0067] <Procedure 5>
[0068] The determined chord "e" in a series of chords is replaced
by the correction chord "e*" determined according to either
procedure 3 or 4.
[0069] c2. Determination of the correction chord "b*"
[0070] The chord "b" is at the end of the block located before the
changed chords "c" and "d". Consequently, in order to determine not
only the chord progression, from the chord "a" to the chord "b",
including the chord "b" which is to be corrected, but also another
chord progression from the chord "b" to the chord "c", it is
necessary to consider a required condition for musical ending
impression in addition to the conditions taken for determination of
the chord "e".
[0071] The detailed procedure of the process during step 106, will
be described below.
[0072] <Procedure >
[0073] Just as the case of the chord "e" determination, the
features of the determined series of chords are detected.
[0074] Procedure 2>
[0075] The chord "b*" is determined by referring to Table 3 shown
below, so that both chord connections from "a" to "b*" and from
"b*" to "c" maybe musically natural, giving a musical ending
impression. The chord progressions in Table 3 are expressed by the
same way as in Table 1, but the priority is determined considering
the ending impression that each chord progression brings. The way
of referring and utilizing Table 3 is also the same as the case of
Procedure 2 for determination of the chord "e*
3TABLE 3 Priority Progression "a"-"b*" Progression "b*"-"c" 1
+4.sup.th perfect - 2nd minor, -2nd major -2.sup.nd minor, -2nd
major + 4th perfect 2 +4.sup.th perfect -3rd minor, -3rd major,
+3rd minor -3rd minor, -3rd major, +4th perfect +3.sup.rd minor 3
+4th augmented( "a" is +4th perfect 7th dim.) 4 +2.sup.nd major
+2nd major +2.sup.nd minor +2nd minor 5 +3.sup.rd major +3rd major
+3.sup.rd minor +3rd minor 6 -3rd minor, -3rd major, -2nd minor,
-2nd major, +5.sup.th perfect +5th perfect -2nd minor, -2nd major,
-3rd minor, -3rd major, +5.sup.th perfect +5th perfect . . . . . .
. . .
[0076] <Procedure 3>
[0077] A similar procedure as the case of the chord "e*"
determination is adopted. If, in the chords listed up in the
procedure 2, is included the chord "b" which was determined by the
process of step 102, the chord "b" is replaced by the correction
chord "b*". If the chord "b" is not found in the list, the
correction chord "b*" is selected from among the listed chords by
finding the one satisfying the features detected in the procedure
1. When there are plural chords satisfying such conditions, one
chord can be selected from among them as the correction chord "b*",
at random or by the user's any idea.
[0078] <Procedure 4>
[0079] In case when the chord "a" is a special (relatively unusual,
e.g., diminish chord "dim"), neither way of chord selection
described in Procedure 2 nor 3 should be adopted. The correction
chord "b*" is then determined according to priority shown in the
following Table 4, although Table 4 contains only one category of
priority.
4TABLE 4 Priority Progression "a"-"b*" Progression "b*"-"c" 1 any
progression +2nd minor
[0080] <Procedure 5>
[0081] The determined chord "b" in a series of chords is then
replaced by the correction chord "b*" determined in the procedure
either 3 or 4.
[0082] c3. A concrete example of the chords "e" and "b" correction
procedure
[0083] Taking an example as shown in FIG. 5, where a part of a
series of chords "a", "b", "c", "d", "e" and "f" assigns
respectively E minor (Em) , A minor (Am) , C major (C), F major
(F), D minor (Dm) and A minor (Am), the concrete procedure of
correcting the chords "e" and "b" will herein below be explained in
detail.
[0084] The chords "a, "b", "e" and "f" are a part of the set of
chord determined by the process of step 102, while the chords "c"
and "d" are the ones changed by the process of step 104 reflecting
features of the motif portion etc. Two detected features of the
series of chords by the procedure 1 are supposed to be "uniquely
diatonic chord" and "triad chord only". The inputted "key" at step
122 is C major.
[0085] The correction procedure of the chord "e" is as follows.
Since the chords at both before and after the chord "e" (Dm) are
"d" (F) and "f" (Am), the following chords, G major (G), G
minor(Gm), G seventh(G7) and G minor seventh(Gm7) are listed up as
candidates to become the chord "e*", by referring Table 1 in the
procedure 2, under the condition that "each interval of the roots
in the progressions "d"-"e*" and "e*"-"f" are in the relationship
of "+2nd major" and "+2nd major", respectively. These chords, G.
Gm,G7 and Gm7 are found with the priority 1 of Table 1. In this
case, because the chord "e"(Dm) is not included in the listed up
chords, G major(G) is nominated and picked up, in the procedure 3,
to become the correction chord "e*", according to the conditions,
"uniquely diatonic chord" and "triad chord only", detected in the
procedure 1. Before the chord "e", the chord "d" which is F
major(F) is placed, and as it does not belong to the special chord
group shown in Table 2, the chord indication in the procedure 4 is
not applied. The chord "e"(Dm) in the series of chords is thus
changed into the correction chord "e*"(G) by the procedure 5, as a
result.
[0086] Now comes the explanation about the correction of the chord
"b". The adjacent chords before and after the chord "b" (Am) are
"a" (Em) and "c" (C). Subsequently, based on Table 3, two following
groups of candidates for the chord "b*" are listed up. The first
group contains G major(G), G minor(Gm), G 7th(G7) and G minor
7th(Gm7), satisfying the condition that "each interval of the roots
in the progressions "a"-"b*" and "b*"-"c" are in the relationship
of "+3rd minor" and "+4th perfect", respectively. The second group
contains A major(A), A minor(Am), A 7th(A7) and A minor 7th(Am7),
satisfying the condition that "each interval of the roots in the
progressions "a"-"b*" and "b*"-"c" are in the relationship of "+4th
perfect" and "+3rd minor", respectively. These listed chords, G,
Gm, G7, Gm7, A, Am, A7and Am7, correspond to the priority 2 in
Table 3. In this case, because the chord "b"(Am) is included in the
listed up chords, this A minor(Am) is nominated and picked up, in
the procedure 3, to become the correction chord "b". Before the
chord "b", the chord "a" which is E minor(Em), is placed, and as it
does not belong to the special chord group shown in Table 4, the
chord indication in the procedure 4 is not applied. As a result,
the chord "b"(Am) in the series of chords rests as it was, even
after the execution of the procedure 5.
[0087] As described in the above, in the first method of chord
correction, the system changes a part of a series of chords, in
order that the chords "b" and "e" adjacent to the changed chord "c"
and "d" have a musically natural connection with the changed chord,
that is the adjacent chords "b" and "e" are changed into the
correction chords "b*" and "e*" respectively. Accordingly, by
applying this first method of chord correction to various systems
such as an automatic composition system which requires to change a
part of a series of given chords, it becomes possible to supply
automatically in a relatively easier way a series of chords which
brings to the music more musically natural impression.
[0088] c4. Examples of variations
[0089] In the above described example of the first method of chord
correction, the chord correction was brought to each one of the
chords, "b" and "e", located at both sides of the changed chords
"c" and "d". However, it is possible to extend the correction to
the chords "a" and "b" and/or the chords "e" and "f". In such case,
a extended table is prepared, at first, which is used to realize a
musically natural chord connection not only with the precedent
chord but also with the following chord. Then, by referring this
table repetitively, plural chords with priority information are
listed up for each one of the chords to be changed. A series of
chords having the highest priority can finally be selected from
among the listed sets of chords. It is also possible to prepare a
table storing a number of series of chords which were already
confirmed to realize a musically natural connection, and then to
extract a suitable series of chords.
[0090] In case when an adequate chord is detected based on given
motif melody, a more natural musical connection can be obtained by
selecting over again a series of chords corresponding to a chord
progression suitable for the detected chords "c" and "d". For
instance, if the conditions "uniquely diatonic chord" or "triad
chord only" are detected based on a motif melody and the series of
chords selected already does not suit to these conditions, a new
series of chords satisfying "uniquely diatonic chord" and "triad
chord only" is then searched and selected over again. The way of
search and selection may be sorting each chord's features
registered beforehand such as "uniquely diatonic chord", "triad
chord only", or could be evaluating chord progression of each
series of chords to extract its peculiar features such as "uniquely
diatonic chord", "triad chord only" and to select eventually a
proper one.
[0091] In the above mentioned example of the first chord
correction, the chords "b" and "e" which are placed before and
after the changed chords "c" and "d", were replaced by the
correction chords "b*" and "e*". But it is also possible to shorten
the length of the chords "b" and "e" and insert the correction
chords at the portion adjacent to the changed chords "c" and "d".
In other words, when a determined series of chords consists of
plural chords "a", "c", "d" and "f" which contain neither the chord
"b" nor "e", and the chords "c" and "d" were changed according to a
motif portion, the latter portion of the chord "a" can be replaced
by the mentioned correction chord "b*", and the earlier portion of
the chord "f" can be replaced by the mentioned correction chord
"e*".
[0092] Another possibility exists in the way where, in the example
of the above mentioned series of chords "a", "b", "c", "d", "e" and
"f" (the chords "c" and "d" were changed according to a motif
portion), a chord having the determined length (e.g., one measure
length) is inserted between the chord "b" and "c" as well as "d"
and "e" without changing the portions before the chord "b" and
after the chord "e", and the inserted chord can be modified so that
it may have a musically natural connection with its adjacent
chords.
[0093] A user can also select a preferred way from among the first
chord correction method, and various variations of chord correction
described in the above.
[0094] Additionally, although any concrete explanation was
abbreviated on the range of chord change and on chord range of the
motif portion, such range can be any number of measures, and the
number of chords within one measure is not limited.
[0095] d. The second chord correction method
[0096] In this paragraph, the second method of chord correction
will be described.
[0097] This second method is to be applied to a system which
generates a melody by an inputted motif melody. The chord
corresponding to the motif portion among the determined series of
chords is replaced by a chord which is more suitable to the motif
melody and has a musically natural connection with its adjacent
chords.
[0098] For this sake, the user starts up the "chord progression
generation program" of FIG. 6 stored in ROM 22 or External Storage
Device 31, instead of the chord progression generation program" of
FIG. 2.
[0099] The execution of chord progression generation program begins
at step 140, and a series of chord is determined at step 142 just
as in the case of the program in FIG. 2. At step 144, CPU 21
displays indication of inputting motif melody on Display Device 13,
according to which the user inputs a motif melody and the part
corresponding to the motif melody in the series of chords by
operating Group of Input Devices for Performance 11 and Group of
Manipulating Knobs 12.
[0100] After the process of step 144, CPU 21 automatically corrects
the part corresponding to the motif melody in the series of chords
to bring a better chord connection at step 146, and finishes
execution of the "chord progression generation program" at step
148.
[0101] Because the process of step 146 is directly related to this
invention, it will be explained afterwards in detail, as "second
chord correction method". The final chord set is thus determined by
the execution of such "chord progression generation program".
[0102] When the second chord progression correction method is
applied to an automatic composition apparatus which composes
melodies automatically, the "automatic composition program" shown
in FIG. 3 is executed. In this case, "chord progression generation
program" of FIG. 6 is applied to the process of chord progression
generation at step 124 in FIG. 3. It is not necessary to input
information on the motif melody to the "chord progression
generation program" at step 122, as the data inputted at step 144
in FIG. 6 can be utilized here.
[0103] Next, the procedures of automatic correction of chords for
the motif melody part will be herein below explained in detail.
[0104] FIG. 7 shows a series of chords . . . , "a", "b", "c", "d",
"e", "f" . . . determined through the process of step 142 just as
the case of the first chord correction method, where the chords "c"
and "d" correspond to the motif melody part inputted at the process
of the step 144. Each chord expressed by "a", "b", "c", "d", "e" or
"f" means one kind of chord whose length(e.g., number of measures
or beats) is not necessarily constant.
[0105] <Procedure 1>
[0106] Just as in the case of the first chord correction method,
the progression of the series of chords determined at the process
of step 142 is analyzed to detect its feature automatically in the
similar way of the first chord correction method.
[0107] <Procedure 2>
[0108] Based on the motif melody inputted at the process of step
144, plural chord sets "c" and "d" (corresponding to the chords "c"
and "d") are listed up as candidates of the chord progression
suitable for the melody. In this case, at least one note of notes
which constitute each chord of the listed up chords is coincident
with at least one note included in the motif melody, and each of
the listed chords should bring a musically natural connection in
the whole series of chords.
[0109] <Procedure 3>
[0110] Among the listed up chords, only the chord sets "c'" and
"d'" which satisfy the feature detected in Procedure 1 are
selected. The number of the listed up chord sets are thus shaken
off, by which only the chords satisfying the condition, for
example, "diatonic chord" and "triad chord", can remain as
candidate.
[0111] <Procedure 4>
[0112] Referring Tables 5 and 6 below, both the correction chord
"c*" which brings a musically natural connection with the precedent
chord "b" and the correction chord "d*" which brings a musically
natural connection with the following chord "e" are determined from
among the already selected chord sets "c'" and "d'" in the
procedure 3. Tables 5 and 6 are made from the data stored in
External Storage Device 31 in the form of table. The data in Table
5 show evaluated values of naturalness of the progression from the
chord "b" to the chord "c*", while those in Table 6 show evaluated
values of naturalness of the progression from the chord "d*" to the
chord "e". The chord progressions in Table 5 and 6 are expressed by
the interval between two roots of a pair of chords and by the
direction of progression between two roots. For instance, "-2nd
major", "+2nd major" and "-3rd minor" signify "root will go down
2nd major intervals", "root will go up 2nd major intervals" and
"root will go down 3rd minor intervals" respectively.
5 TABLE 5 Progression Evaluated value "b"-"c`" ("b"-"c*") 4 -2nd
minor, +2nd minor, + 4th perfect 3 -3rd minor, + 3rd major, -3rd
minor . . . . . .
[0113]
6 TABLE 6 Progression Evaluated value "d`"-"e" ("d*"-"e") 4 -2nd
major, -3rd major, -3rd minor 3 -2nd minor, +2nd major, +5th
perfect . . . . . .
[0114] The steps to determine the correction chords "c*" and "d*"
may be more concretely described as follows.
[0115] Each of the chord sets selected in the procedure 3 is
handled one by one, in order. The progression from the chord "b"
designated from among the series of chords at the process of step
142, to the chord "c'" (corresponding to the chord "c*") which is
an earlier-coming part of the selected two chord sets "c" and "d'",
is evaluated from the viewpoint of musical naturalness in
connection portion. The evaluation can be executed by referring
Table 5 for the two roots, "b"-"c'". On the other hand, the
progression from the chord "d'"(corresponding to the chord "d*")
which is an later-coming part of the selected two chord sets "c"
and "d'", to the chord "e" designated from among the series of
chords determined at the process of step 142, is similarly
evaluated. The evaluation can be made by referring Table 6 for the
two roots, "d'"-"e'". The two evaluated values are summed to be
temporarily memorized. Then, among plural chords sets selected in
the procedure 3, the chord sets "c'" and "d'" having the largest
summed value are determined to be adopted as the correction chord
sets "c*" and "d*" by referring Tables 5 and 6. If there are plural
chord sets having the same largest summed value, the user can
choose one of them at random, or determine it by his any
preference.
[0116] <Procedure 5>
[0117] When the chord "b" and/or "e" is one of the special
chords(e.g., diminish chord), the above mentioned way of chord set
selection in Procedure 3 and 4 should not be adopted, but the
evaluation values placed in Tables 7 and 8 shown below are
available. Tables 7 and 8 are also made from the data stored in
External Storage Device 31 in the form of table. The data in Table
7 show evaluated values of naturalness of the progression from the
chord "b" to the chord "c*" when the chord "b" is one of the
special kinds of chord, while those in Table 8 show evaluated
values of naturalness of the progression from the chord "d*" to the
chord "e" when the chord "e" is one of the special kinds of chord.
Just as the case of Tables 5 and 6, the chord progressions in Table
7 and 8 are expressed by the interval between two roots of a pair
of chords and by the direction of progression between two
roots.
7 TABLE 7 Progression Evaluated value "b"-"c`" ("b"-"c*") 4
+2.sup.nd minor 3 -2.sup.nd minor . . . . . .
[0118]
8 TABLE 8 Progression Evaluated value "d`"-"e" ("d*"-"e") 4 +2nd
minor 3 +2nd major . . . . . .
[0119] The determining steps of the evaluated value will be more
concretely described herein below.
[0120] If the chord "b" in the series of chords determined at step
142 is one of the special kind of chords, an evaluated value
corresponding to the chord progression "b"-"c" is taken from Table
7. If the chord "e" in the chord set is one of the special kinds of
chords, an evaluated value corresponding to the chord progression
"d'"-"e" is taken from Table 8. Then, the determination of the
chord sets "c*" and "d*" is made after summing the two values
according to the described procedure 4.
[0121] This paragraph will explain the process of chord correction
in the procedures 1-5 by citing a practical example, where two
chords "b" and "e" among the chords, "a", "b", "c", "d", "e", "f"
which are a part of the series of chords determined at the process
of step 142, are "B minor 7th flat 5" (Bm7b5) and "A minor" (Am)
respectively, and the chords "c"]and "d" are to be corrected. The
chords "c" and "d" are the part corresponding to the motif melody.
Each of them occupies one measure, and the two chords cover two
measures. As motif melody, two chords "E" and "G" are given to the
first measure and "A", "G" to the second measure. The key inputted
at the process of step 122 is C major.
[0122] The feature of the series of chords detected by the
procedure 1 is "uniquely diatonic chord", and 7(seven) chord sets
"Am7"-"Dm7", "Em"-"C6", "C7"-"F", "G6"-"Am", "C"-"F", "Em"-"D7" and
"A7"-"Dm7" are selected as candidate for the correction chord sets
"c*"-"d*" determined by the motif melody in the procedure 2. Then,
they are shaken off in the procedure 3 according to the feature of
the chord "uniquely diatonic chord", and four chord sets,
"Am7"-"Dm7", "Em"-"C6", "G6"-"Am" and "C"-"F" are picked up.
[0123] In the procedure 4, the chord connection from the chord "b"
(Bm7b5) to chords at the first measure in each of the four chord
sets, "Am7", "Em", "G6" and "C" respectively, are evaluated. The
evaluated values are 4, 4, 3 and 0 respectively, because intervals
between two roots of each chord progression are <-2nd major>,
<+4th perfect>, <-3rd major> and <+2nd minor>
respectively. On the other hand, since the chord of the second
measure in each of the four chord sets are "Dm7", "C6", "Am" and
"F", the evaluated values from each of them to the chord "e" (Am)
are 3, 4, 0 and 0 respectively, because intervals between two roots
of each chord progression are <+5th perfect>, <-3rd
minor>, <1(the same)>and <+3rd major> respectively.
The evaluated value "0" is given to the chord connections which are
not found in Tables 5 and 6.
[0124] Four sets of evaluated values for the four chord sets
"Am7"-"Dm7", "Em"-"C6", "G6"-"Am" and "C"-"F" are then summed
respectively. The result is 7,8,3 and 0 respectively. Consequently,
the chord set "Em"-"C6" corresponding to the maximum value 8 is
finally chosen as the correction chord set "c*"-"d*". In this
example. Since any special chord(like diminish chord) is not found
in the chord "b" or "e", it is unnecessary to refer Table 7 or8 in
the procedure 5.
[0125] If viewed briefly, the second chord correction method
comprises the following steps. For a system in which a motif melody
is given to a series of given chords, the chord sets "c*" and "d*"
which are appropriate to the motif melody and have a musically
natural connection with the adjacent chords are firstly determined.
Then, the chords "c" and "d" corresponding to the motif melody are
replaced by the determined chord sets "c*" and "d*". Accordingly,
in an automatic composition system and the like, it becomes
relatively easy to obtain a musically natural series of chords by
using the second chord correction method.
[0126] In the described case, the chord set corresponding to a
motif melody was constituted of two chords, but this second chord
correction method is also applicable to cases when the chord set is
constituted of one or more than two chords. In case of one chord,
the connection between the one chord and its adjacent chords in the
determined chord set is evaluated in the above explained way.
While, in case of three chords, two connections, between each one
of two chords located at extremities of the three chords and its
respective adjacent chord in the determined chord set, are
evaluated in the same way.
[0127] In the described second chord correction method, the chord
set is determined by reason of having the maximal summed value.
However, if the summed value does not attain the predetermined
value, determination of the series of chords can be exercised over
again, or the chords, adjacent to the part corresponding to the
motif melody among the determined series of chords, can be
corrected also following the first chord correction method.
[0128] In the second chord correction method, the chord connections
at two extremities of the chord set corresponding to the motif
melody were considered, but, in case when a motif portion comes at
the extremity of the music, e.g., at the top of music, it is not
necessary to take the chord connection at the concerned point into
account.
[0129] e. Application of chord correction to automatic
composition
[0130] A music is generally composed so that each of its sections
may have original musicality as well as have ups and downs as a
whole. In the following paragraph, the term "musical highlight
(="musically highlighted portion" utilized already in this
document)" regarding the original musicality will be described to
clarify its definition.
[0131] The "musical highlight" means "a portion of music whose
musical expression is more original and different from other
portions". It includes, for instance, a portion of climax, a
portion of depression, and a modest portion to make intentionally a
climax or a depression more outstanding. It would be possible to
utilize some other term than the "musical highlight" for a musical
section with said original musicality. Moreover, various kinds of
terms can be assigned to a plurality of musical sections having
their respective and different musical originalities. In other
words, the portion of "musical highlight" can also be defined as
"an especially marked section of a music".
[0132] In the embodiment described in the following, the term
"musical highlight" is adopted to express, as an example, a portion
of climax or uprush in a music, and not other original
musicalities. In order to utilize the portion of "musical
highlight" (section having a special original musicality) widely in
composition process, it is copied to put it at the beginning of the
music (music of "musical highlight"-beginning), to put it at the
end of music(music of "musical highlight"-ending), or to repeat it
plural times at the end of music(music of repetitive-"music
highlight"-ending). In this example, the first and second chord
correction method above described are adapted to an automatic
composition system which composes a music comprising the "musical
highlight".
[0133] In FIG. 9, is shown an example of determination process of
music structure in an automatic composition system. At "Intro 1"
and "Ending 9", a user can choose one preferred type among plural
candidates. For instance, outstanding type accompaniment or modest
type accompaniment can be chosen at beginning and/or ending of a
music to be composed. Sections 3, 4 and 6, 7 signify the principal
portion of a music, usually called "first chorus" and "second
chorus" respectively. If the second chorus is unnecessary, user can
delete the section.
[0134] The section called here "musical highlight" generally comes
after the early appearing part of the principal portion( at each
section of B in FIG. 9). In order to make use of the "musical
highlight" in a music, the following way of music structure
determination can be taken.
[0135] In the first way, the "musical highlight" comes at the
beginning to give a climax of music at its starting moment, while
in the second way it comes at the ending to end the music with a
climax. In the third way, the "musical highlight" is repeatedly
used in a music. FIG. 9 shows a case where both the second and the
third ways are adopted, namely, repeating the "musical highlight"
during and at the end of a music. Sometimes, a transposed "music
highlight" is repeated to give a dramatic effect to the music. When
"fade out" is indicated at ending portion, the music ends with
repeated its ending portion but fading out gradually. In this case,
if "repetition of musical highlight" is indicated, the music ends
with repeated "musical highlight" fading out.
[0136] Next, an automatic composition system which applies the
above described method will be explained. This automatic
composition system is constructed as shown in FIG. 1, whose
principal function is controlled by a micro-computer. An automatic
composition program shown in FIG. 10 is stored in ROM 22 or
External Storage Device 31 to be executed by CPU 21.
[0137] The execution of the program is started up at step 200.
After starting up the program, just as the process of step 122 of
FIG. 3, the data for melody generation are inputted at step 202. To
generate a part of the "musical highlight" in a music which is
going to be composed, are inputted such melody generation data as
melody data for the "musical highlight", data indicating the
position of the "musical highlight" in the music, pitch data
enabling the pitch at the "musical highlight" higher than other
portions in the music so that the "musical highlight" may become
still more impressive. Thus, besides the basic melody generation
data for portions of 1st chorus melodies A, B, act tune, 2nd chorus
melodies A,B etc., additional melody generation data which indicate
that the melody portion B is "musical highlight" portion are given,
as shown in 3-5 in FIG. 9.
[0138] At step 204, a series of chords is inputted just as the
process of step 102. In this case, however, chord progressions with
many tension chords are adopted to the part corresponding to the
"musical highlight" so that its accompaniment may be showy.
[0139] After processing at steps 202 and 204, CPU 21 displays on
Display Device 13 a message requesting the user to indicate a
section which should include a "musical highlight" at step 206. An
example of such displayed message is seen in FIG. 11. The displayed
message inquires the user whether the "Intro" section should be
outstanding type, modest type, or it should be eliminated. It asks
also whether the melody portion of the 2nd should remain or be
deleted, whether the "musical highlight" be at the beginning, or be
repeated, whether the repeated "musical highlight" should be
transposed (and to which music key, if yes), whether the ending
section should be outstanding or modest, and whether the ending
should be faded out or not.
[0140] By answering to each of such inquiries, the user designates,
by handling Group of Manipulating Knobs 12, the appropriate
sections which constitute a complete music. For instance, if the
black circled features in FIG. 11 are selected, it means that the
composed music takes the structure having plural sections shown in
FIG. 9. However, there is a high possibility that the music of this
case has not desired musically natural connections in the series of
chords obtained after having designated sections such as "musical
highlight" at step 206, because the chord set corresponding to
melody section B is copied to paste both after "Intro" and before
"Ending" by the indications of "musical highlight" at the beginning
and its repetition. Namely, the series of chords determined at step
204 may have to be changed.
[0141] Accordingly, to cope with such a possible defect, the
unnatural chord connection is corrected at step 208. In the chord
correction process, the first and second chord correction method
above described can be applied. Once such correction method is
applied, the user need not worry any more about naturalness of
chord connection even when he adopts "musical highlight" at several
sections of the music.
[0142] At next steps 210 and 212, the music scale mode is detected,
just as in case of steps 126 and 128 in FIG. 3, then the melody is
eventually generated. The execution of this automatic composition
program which can thus compose automatically a music containing
melodies and chords with appropriate portions of "musical
highlight" is terminated at step 130.
[0143] With such an automatic composition method, a music having
its climax at several points and having full of variety can be
easily constructed by designating a given "musical highlight" at
the beginning and/or at the end, or by repeating it. The "musical
highlight" can become still more variant by adding transposition
data to the inputted melody generation data for the additionally
established "musical highlight" portion, which makes possible to
compose automatically a musically rich music. At the process of
step 208, the connection portion between the chord determined for
the added "musical highlight" portion and the series of given
chords is corrected so as to bring a musical naturalness. Under
such condition, even when a "musical highlight" portion is added, a
given chord progression does not become unnatural, which enables
the system to generate automatically a music of high quality.
[0144] In the above described example of automatic composition, a
musical structure is established by operating Group of Manipulating
Knobs 12 according to displayed message on Display Unit 13 for
music structure selection. But, instead of this electronic way, it
is also possible to dispose the mechanical switches identical to
the displayed status as shown in FIG. 11, and then, manipulating
such switches, to establish a music structure.
[0145] In the various kinds of embodiment above described, the
present invention is applied, in common, to the musical sound
generation apparatus whose structure is shown in FIG. 1. However,
this invention can be applied not only to this type of embodiment,
but also to many other types such as electronic musical instrument,
PC apparatus combined with application software, karaoke apparatus,
PC game apparatus, portable communication terminals like portable
personal telephone, and automatic playing piano. In case of
portable communication terminal, for instance, all aimed functions
cannot always be realized by the terminal only. Then, in order to
complete it, it is possible to let a part of the functions go to a
server so that the whole system consisting of terminal and server
can realize the aimed functions.
[0146] Additionally, in case of an embodiment of electronic musical
instrument type, the type is not limited to a keyboard instrument,
but can be other types such as stringed instrument type, wind
instrument type, and percussion instrument type. Moreover, not
limited to the electronic musical instrument integrating a sound
source apparatus and automatic play apparatus and other
apparatuses, it can be composed of separate apparatuses connected
by various transmission means such as MIDI devices, other kinds of
network.
[0147] Lastly, this invention may be practiced or embodied in still
other ways without departing from the spirit or essential character
thereof as described heretofore. Therefore the preferred embodiment
described herein is illustrative and not restrictive, the scope of
the invention being indicated by the appended claims and all
variations which come within the meaning of the claims are intended
to be embraced therein.
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